feat(supervisor): add flag to enable compute snapshots

Gates snapshot/restore behaviour independently of compute mode.
When disabled, VMs won't receive the metadata URL and suspend/restore
are no-ops. Defaults to off so compute mode can be used without snapshots.

Author: nicktrn

apps/supervisor/src/env.ts

@@ -81,6 +81,7 @@ const Env = z.object({
   COMPUTE_GATEWAY_URL: z.string().url().optional(),
   COMPUTE_GATEWAY_AUTH_TOKEN: z.string().optional(),
   COMPUTE_GATEWAY_TIMEOUT_MS: z.coerce.number().int().default(30_000),
+  COMPUTE_SNAPSHOTS_ENABLED: BoolEnv.default(false),
 
   // Kubernetes settings
   KUBERNETES_FORCE_ENABLED: BoolEnv.default(false),

apps/supervisor/src/index.ts

@@ -223,7 +223,7 @@ class ManagedSupervisor {
       if (checkpoint) {
         this.logger.log("Restoring run", { runId: message.run.id });
 
-        if (this.isComputeMode && this.computeManager) {
+        if (this.isComputeMode && this.computeManager && env.COMPUTE_SNAPSHOTS_ENABLED) {
           try {
             // Derive runnerId unique per restore cycle (matches iceman's pattern)
             const runIdShort = message.run.friendlyId.replace("run_", "");

apps/supervisor/src/workloadManager/compute.ts

@@ -51,7 +51,7 @@ export class ComputeWorkloadManager implements WorkloadManager {
       envVars.TRIGGER_WARM_START_URL = this.opts.warmStartUrl;
     }
 
-    if (this.opts.metadataUrl) {
+    if (env.COMPUTE_SNAPSHOTS_ENABLED && this.opts.metadataUrl) {
       envVars.TRIGGER_METADATA_URL = this.opts.metadataUrl;
     }
 
@@ -266,17 +266,21 @@ export class ComputeWorkloadManager implements WorkloadManager {
       TRIGGER_WORKER_INSTANCE_NAME: env.TRIGGER_WORKER_INSTANCE_NAME,
     };
 
+    const body = {
+      name: opts.runnerId,
+      metadata,
+      cpu: opts.machine.cpu,
+      memory_mb: opts.machine.memory * 1024,
+    };
+
+    this.logger.debug("restore request body", { url, body });
+
     const [error, response] = await tryCatch(
       fetch(url, {
         method: "POST",
         headers: this.authHeaders,
         signal: AbortSignal.timeout(this.opts.gatewayTimeoutMs),
-        body: JSON.stringify({
-          name: opts.runnerId,
-          metadata,
-          cpu: opts.machine.cpu,
-          memory_mb: opts.machine.memory * 1024,
-        }),
+        body: JSON.stringify(body),
       })
     );
 

apps/supervisor/src/workloadServer/index.ts

@@ -263,7 +263,7 @@ export class WorkloadServer extends EventEmitter<WorkloadServerEvents> {
               return;
             }
 
-            if (this.computeManager) {
+            if (this.computeManager && env.COMPUTE_SNAPSHOTS_ENABLED) {
               // Compute mode: fire-and-forget snapshot with callback
               reply.json({ ok: true } satisfies WorkloadSuspendRunResponseBody, false, 202);